Adolescents seeking orthodontic treatment frequently appear to be motivated by social and psychological factors. These include the anticipation of others' negative reactions to their dental-facial appearance and the effects of this anticipation on psychosocial functioning. An estimated 80 percent of those seeking treatment are reported to be primarily concerned about facial esthetics, rather than problems of physical functions. Since approximately 70 percent of the population has some form of dentofacial malrelations, the potential demands for treatment based on psychosocial need is great. The use of public funds to provide orthodontic treatment has further increased the need to identify problems of psychosocial functioning which could be alleviated by orthodontic treatment. Yet the psychosocial effects of orthodontic treatment have not been adequately demonstrated in systematic research. The proposed study utilizes a randomized control group design to assess these effects. Eighty-eight adolescents, 12 to 13 years old, with permanent dentition, who are seeking orthodontic treatment, will comprise the study sample. These subjects will be randomly assigned to the Treatment Group or Control Group. A battery of psychosocial instruments, including measures of dental-facial attractiveness, self-perception of occlusion, self-image, social behavior, and parents' perceptions of their children's occlusion, will be administered to chilren and/or their mothers just prior to initiating orthodontic treatment for the Treatment Group. The measures will be repeated twice during the course of treatment and again immediately, six months, and one year after the removal of fixed appliances. The Treatment and Control Groups will be compared on these measures, with pretreatment measures used as covariables in a series of univariate analyses. Orthodontic treatment will be provided for the Control Group after all data are collected. This research will provide the first data from a controlled study regarding the extent to which orthodontic correction can be expected to improve psychological and social functioning in adolescents.